WASHINGTON — One mother stopped watching “ER” reruns when her preschooler tried to give her little brother CPR. Another mom laughed that her 15-month-old sang the McDonald’s jingle — “ba, ba, boppa, ba” — every time they drove past the golden arches.

One-third of the nation’s youngest children — babies through age 6 — live in homes where the television is on almost all the time, says a study that highlights the immense disconnect between what pediatricians advise and what parents allow.

TV in the bedroom is not even that rare for the littlest tots anymore. Almost one child in five under 2 has a set, even though the American Academy of Pediatrics advises against any TV watching at that age.

Eight in 10 children younger than 6 watch TV, play video games or use the computer on a typical day. They average about two hours of screen time, compared with 48 minutes when they are being read to, the Kaiser Family Foundation concludes in a study released May 24.

The number of youngsters glued to the screen has not changed much since the foundation’s first report on the topic in 2003.

But in this follow-up, Kaiser asked parents — in a survey and in focus-group sessions — why they and their children use TV and other electronic media the way they do.

“I had this sense of kids clamoring to use media and parents trying to keep their finger in the dam,” lead researcher Victoria Rideout said. “I found that not to be a very accurate picture in most cases.”

Instead, a generation of parents raised on TV is largely encouraging the early use of television, video games and computers by their own children, often starting in infancy.

These parents say TV teaches how to share and the ABCs when they do not have the time. Television provides time for parents to cook or take a shower. They use screen time as a reward or, paradoxically, to help kids wind down at bedtime.

“There’s this enthusiasm and tremendous lack of concern” about media use, Rideout said.

“It’s just background noise,” said one Colorado woman who has a preschooler and who keeps the TV on most of the day. The study did not identify people in the focus group by name.

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Where some parents limited scary shows or video games, others found youngsters unfazed. “It’s something gory, but it doesn’t seem to bother her,” said a California mother whose toddler joined her on the couch for “CSI: Crime Scene Investigation.”

Can't get by without it
Despite studies that link bedroom TVs to kids’ sleep problems, the most common reason cited for giving children their own set was that it freed up other TVs so parents or their other children could watch their shows.

The report by the California-based foundation, which analyzes health care issues, comes at a time of great debate about the impact of TV and other multimedia on youngsters. Specialists called together by the National Institutes of Health recently urged more research on how electronic media affect children at different ages.

Those specialists sigh at the notion that parents could not get by without TV.

“People have made dinner for millenia, but we’ve only had television for 50 years,” said Dr. Dimitri Christakas of the University of Washington. “Television’s not inherently good or bad. ... The real goal now has to be not to de-technologize childhood, but how to optimize children’s experiences” with it.

The pediatrics group recommends no TV or other electronic media for kids younger than 2 — advice that just 26 percent of parents followed, Kaiser found — and no more than two hours of total “screen time” daily for older children.

The organization is not anti-TV, said Dr. Daniel Broughton of the Mayo Clinic, an academy member who co-wrote the recommendations. But before age 2 is time of the brain’s most rapid development, and interaction — the live give-and-take that TV cannot provide — is crucial during that period, he said.

Some studies also link TV watching at younger ages to youngsters’ attention disorders.

After a child reaches 2, the idea is to balance a little TV with riding bikes, playing with friends, household chores and the other activities of childhood, Broughton said.

“We want parents to watch with their kids,” he added. One reason is that viewing ethnic stereotypes or bad behavior on TV can become instructive, when parents explain why children should not copy what they saw.

In addition to the focus groups, the Kaiser report is based on results of a national, random telephone survey last fall of 1,051 parents of children 6 months to 6 years. The margin of error is plus or minus 3 percentage points.